Azo compounds



Patented Apr. 12, 1938 PATIENT OFFICE AZO COMPOUNDS Fritz Mietzsch andJos berfeld, Germany,

of Klarer, Wuppertal-Elassignorsv to Winthrop Chemical Company, Inc.,New York, N. Y., a

corporation of New York No Drawing. Original 1933, Serial N0. 702,427.

plication March 27,

application December 14,

Divided and this ap- 1936, Serial No. 71,347.

In Germany November 30, 1933 6 Claims.

This invention relates to azo compounds which are soluble in alkalinesolution and display a bactericidal action, and to a process ofpreparing the same.

In accordance with the present invention alkali-soluble azo compoundsdisplaying a bactericidal action are obtainable by the manufacture ofthe compounds of the general formula:

wherein R1 stands for a para-sulfamide or disulfamide substitutedradical of the benzene series, and R2 stands for a cyclic radicalcontaining nitrogen in basic linkage, that is for an aminobenzenc oraminonaphthalene radical which contains at least one hydroxyl group. Inthe new azo compounds the amino group of the sulfamide group may be aprimary, secondary or tertiary amino group. It may, for instance, besubstituted by saturated or unsaturated alkyl or cycloalkyl groups, suchas methyl, ethyl, allyl, butyl, isoamyl, cyclohexenyl, or by aralkylgroups, such as benzyl and phenylethyl. The two hydrogen atoms of theamino group may also be replaced by an alkylene group in which case thenitrogen atom of the sulfamide group forms a hydrogenated heterocyclicring system with the alkylene group, for instance, a pyrrolidyl orpiperidyl ring. The new compounds may contain besides the abovespecified characteristic groups other substituents, such as alkyl,halogen, hydroxyl, alkoxy, phenoxy and the nitro group, but free acidgroups should not be present. The amino groups attached to the onenucleus of the azo compounds may be substituted, for instance,

by alkyl groups.

In accordance with the present invention the alkali-soluble azocompounds of the kind specifiecl are obtainable by reacting upon anaminobenzene or aminonaphthalene compound which contains at least onehydroxyl group with a parasulfamide or a disulfamide diazo compound ofthe benzene series, whereby the reacting components may be furthersubstituted in the manner above indicated. The reaction isadvantageously carried out in the presence of water at a lowtemperature, say at about 20 C. or below. The azo compounds thusobtainable are'colored powders which are insoluble in water but formwith mineral acids, such as hydrochloric, hydrobromic, sulfuric andalkyl sulfonic acids salts which dissolve more or less inwater. Sincethe new azo compounds contain a phenolic hydroxyl group they dissolvealso in caustic alkalies. In view of their remarkable bactericidalaction the new compounds have proved active in the treatment ofinfectious diseases.

The invention is further illustrated by the following example withoutbeing restricted thereto:

Ea'ample 1.20.8 grams of the hydrochloride of4-amino-benzene-sulfonoamide are diazotized in hydrochloric acidsolution by means of 6.9 grams of sodium nitrite. A solution of 10.9grams of 3- aminophenol in excess caustic alkali lye is added to thediazo solution. The coupling reaction immediately takes place. From thered brown solution the 4'-sulfonoamide-2-amino-4-hydroxyazo-benzene isobtained by means of acetic acid as a brown precipitate which, afterprecipitation from its aqueous solution in caustic soda lye by means ofacetic acid, melts at 106 C.

When using instead of B-aminophenol, 1.8- amino-naphthol in the abovereaction, 4'- sulfoncamide-benzene-azo -4-hydroxy 5 aminonaphthalene isobtained in the form of a blackishbrown precipitate melting at 232 C.while decomposing. The new product dissolves in aqueous caustic sodasolution with violet coloration.

If the coupling of the 4-sulfonoamide-diazobenzene with 3-aminophenol isperformed in acid solution, the hydrochloride of the4-sulfonoamide-2-hydroxy-4-amino-azo-benzene is obtained as a brick redpowder which is soluble in caustic soda lye with cherry red colorationmelting at 228 C.

This is a division of our copending application for Letters PatentSerial No. 702,427, filed December 14, 1933.

We claim:

1. Alkali-soluble azo compounds of the general formula:

wherein R1 stands for a cyclic radical selected from the groupconsisting of para-sulfamide and disulfamide substituted radicals of thebenzene series, and R2 stands for a cyclic radical containing nitrogenin basic linkage, which cyclic radical is selected from the groupconsisting of hydroxy-amino benzenes and the corresponding N-alkylatedcompounds, which azo compounds form water-soluble salts with mineralacids or caustic alkalies.

2. Alkali-soluble azo compounds of the general formula:

wherein R2 stands for a cyclic radical selected from the groupconsisting of hydroxy-amino benzenes and the corresponding N-alkylatedcompounds, and :01 and :112 stand for hydrogen, which azo compounds formWater-soluble salts with mineral acids or caustic alkalies.

5 3. Alkali-soluble azo compounds of the general formula:

v N\ 10 R1N=NQ I;

wherein R1 stands for a cyclic radical selected 15 from the groupconsisting of para-sulfamide and disulfamide substituted radicals ofthe'benzene series, an and x2 stand for hydrogen, which azo compoundsform Water-soluble salts with mineral acids or caustic alkalies.

4. Alkali-soluble azo compounds of the general formula:

\ /N O a S N=N n OH wherein an and 0:2 stand for hydrogen, which azocompounds form water-soluble salts with mineral acids or causticalkalies.

5. The process which comprises reacting upon an amino-hydroxybenzenewith a diazo compound selectd from the group consisting of parasulfamideand disulfamide diazo compounds of the benzene series.

6. The process which comprises reacting upon an amino-hydroxy benzenewith a para-sulfamido benzene diazo compound.

FRITZ MIETZSCH. JOSEF KLARER.

